1.
Agar plate
–
An agar plate is a Petri dish that contains a growth medium used to culture microorganisms or small plants like the moss Physcomitrella patens. Selective growth compounds may also be added to the media, such as antibiotics, individual microorganisms placed on the plate will grow into individual colonies, each a clone genetically identical to the individual ancestor organism. Some commonly used agar plate types are, Blood agar plates contain mammalian blood, bAPs are enriched, differential media used to isolate fastidious organisms and detect hemolytic activity. β-Hemolytic activity will show lysis and complete digestion of red blood cell contents surrounding a colony, α-Hemolysis will only cause partial lysis of the red blood cells and will appear green or brown, due to the conversion of hemoglobin to methemoglobin. An example of this would be Streptococcus viridans, γ-Hemolysis is the term referring to a lack of hemolytic activity. BAPs also contain meat extract, tryptone, sodium chloride, chocolate agar is a type of blood agar plate in which the blood cells have been lysed by heating the cells to 56 °C. It is used for growing fastidious respiratory bacteria, such as Haemophilus influenzae, no chocolate is actually contained in the plate, it is named for the coloration only. Horse blood agar is a type of blood-enriched microbiological culture media, as it is enriched, it allows the growth of certain fastidious bacteria, and allows indication of haemolytic activity in these bacterial cultures. Thayer-Martin agar is a chocolate agar designed to isolate Neisseria gonorrhoeae, thiosulfate-citrate-bile salts-sucrose agar enhances growth of Vibrio spp. including Vibrio cholerae. Granada medium is used to isolate and differentiate group B Streptococcus, Streptococcus agalactiae from clinical samples and it grows in Granada medium as red colonies and most of accompanying bacteria are inhibited. Hektoen enteric agar is designed to isolate and recover fecal bacteria belonging to the Enterobacteriaceae family and it is particularly useful in isolating Salmonella and Shigella. Lysogeny broth MacConkey agar is a selective and differential medium used to differentiate between Gram-negative bacteria while inhibiting the growth of Gram-positive bacteria, the addition of bile salts and crystal violet to the agar inhibits the growth of most Gram-positive bacteria, making MacConkey agar selective. Lactose and neutral red are added to differentiate the lactose fermenters, an alternative medium, eosin methylene blue serves a similar purpose. Mannitol salt agar is also a selective and differential medium, the mannitol indicates organisms that ferment mannitol, mannitol fermentation produces lactic acid, lowering the pH and turning the plate yellow. The salt is to select for halophiles, organisms that cannot withstand a high salt content are unable to grow well, mueller-Hinton agar contains beef infusion, peptone, and starch, and is used primarily for antibiotic susceptibility testing. It can be in a form of blood agar, nutrient agar is usually used for growth of nonfastidious organisms and observation of pigment production. It is safe to use in science laboratories because it does not selectively grow pathogenic bacteria. Önöz agar allows more rapid bacteriological diagnosis, as Salmonella and Shigella colonies can be clearly and reliably differentiated from other Enterobacteriaceae, the yields of Salmonella from stool samples obtained, when using this medium, are higher than those obtained with LEIFSON agar or Salmonella–Shigella agar
Agar plate
–
An agar plate being viewed in an electronic
colony counter
Agar plate
–
Red blood cells on an agar plate are used to diagnose
infection. On the left is a positive
Staphylococcus infection, on the right a positive
Streptococcus culture.
Agar plate
–
Hemolyses of
Streptococcus spp. (left) α-hemolysis (
S. mitis); (middle) β-hemolysis (
S. pyogenes); (right) γ-hemolysis (= nonhemolytic,
S. salivarius)
Agar plate
–
Four types of agar plate demonstrating differential growth depending on bacterial
metabolism
2.
Microorganism
–
A microorganism or microbe is a microscopic organism, which may be single-celled or multicellular. The study of microorganisms is called microbiology, a subject that began with the discovery of microorganisms in 1674 by Antonie van Leeuwenhoek, microorganisms are very diverse and include all bacteria, archaea and most protozoa. This group also contains some fungi, algae, and some such as rotifers. Many macroscopic animals and plants have microscopic juvenile stages, some microbiologists classify viruses and viroids as microorganisms, but others consider these as nonliving. In July 2016, scientists identified a set of 355 genes from the last universal ancestor of all life, including microorganisms. Microorganisms, under certain test conditions, have observed to thrive in the vacuum of outer space. Microorganisms likely far outweigh all other living things combined, the mass of prokaryote microorganisms including the bacteria and archaea may be as much as 0.8 trillion tons of carbon, out of the total biomass of between 1 and 4 trillion tons. Microorganisms appear to thrive in the Mariana Trench, the deepest spot in the Earths oceans, in August 2014, scientists confirmed the existence of microorganisms living 800 m below the ice of Antarctica. According to one researcher, You can find microbes everywhere — theyre extremely adaptable to conditions, microorganisms are crucial to nutrient recycling in ecosystems as they act as decomposers. As some microorganisms can fix nitrogen, they are a part of the nitrogen cycle. Microorganisms are also exploited in biotechnology, both in food and beverage preparation, and in modern technologies based on genetic engineering. A small proportion of microorganisms are pathogenic, causing disease and even death in plants, Robert Hooke coined the term cell after viewing plant cells under his microscope. Antonie Van Leeuwenhoek was one of the first people to observe microorganisms in 1673, later, in the 19th century, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In 1876 Robert Koch discovered that microorganisms cause diseases, single-celled microorganisms were the first forms of life to develop on Earth, approximately 3–4 billion years ago. Further evolution was slow, and for about 3 billion years in the Precambrian eon, so, for most of the history of life on Earth, the only forms of life were microorganisms. Bacteria, algae and fungi have been identified in amber that is 220 million years old, microorganisms tend to have a relatively fast rate of evolution. Most microorganisms can reproduce rapidly, and bacteria are able to freely exchange genes through conjugation, transformation and transduction. This rapid evolution is important in medicine, as it has led to the development of multidrug resistant pathogenic bacteria, superbugs, the possible existence of microorganisms was discussed for many centuries before their discovery in the 17th century
Microorganism
–
A cluster of
Escherichia coli bacteria magnified 10,000 times
Microorganism
–
Antonie van Leeuwenhoek, the first
microbiologist and the first to observe microorganisms using a
microscope
Microorganism
–
Lazzaro Spallanzani showed that boiling a broth stopped it from decaying
Microorganism
–
Louis Pasteur showed that Spallanzani's findings held even if air could enter through a filter that kept particles out
3.
Ancient Greeks
–
Ancient Greece was a civilization belonging to a period of Greek history from the Greek Dark Ages of the 12th-9th centuries BC to the end of antiquity. Immediately following this period was the beginning of the Early Middle Ages and this was followed by the period of Classical Greece, an era that began with the Greco-Persian Wars, lasting from the 5th to 4th centuries BC. Due to the conquests by Alexander the Great of Macedonia, Hellenistic civilization flourished from Central Asia to the end of the Mediterranean Sea. Classical Greek culture, especially philosophy, had a influence on ancient Rome. For this reason Classical Greece is generally considered to be the culture which provided the foundation of modern Western culture and is considered the cradle of Western civilization. Classical Antiquity in the Mediterranean region is considered to have begun in the 8th century BC. Classical Antiquity in Greece is preceded by the Greek Dark Ages and this period is succeeded, around the 8th century BC, by the Orientalizing Period during which a strong influence of Syro-Hittite, Jewish, Assyrian, Phoenician and Egyptian cultures becomes apparent. The end of the Dark Ages is also dated to 776 BC. The Archaic period gives way to the Classical period around 500 BC, Ancient Periods Astronomical year numbering Dates are approximate, consult particular article for details The history of Greece during Classical Antiquity may be subdivided into five major periods. The earliest of these is the Archaic period, in which artists made larger free-standing sculptures in stiff, the Archaic period is often taken to end with the overthrow of the last tyrant of Athens and the start of Athenian Democracy in 508 BC. It was followed by the Classical period, characterized by a style which was considered by observers to be exemplary, i. e. classical, as shown in the Parthenon. This period saw the Greco-Persian Wars and the Rise of Macedon, following the Classical period was the Hellenistic period, during which Greek culture and power expanded into the Near and Middle East. This period begins with the death of Alexander and ends with the Roman conquest, Herodotus is widely known as the father of history, his Histories are eponymous of the entire field. Herodotus was succeeded by authors such as Thucydides, Xenophon, Demosthenes, Plato, most of these authors were either Athenian or pro-Athenian, which is why far more is known about the history and politics of Athens than those of many other cities. Their scope is limited by a focus on political, military and diplomatic history, ignoring economic. In the 8th century BC, Greece began to emerge from the Dark Ages which followed the fall of the Mycenaean civilization, literacy had been lost and Mycenaean script forgotten, but the Greeks adopted the Phoenician alphabet, modifying it to create the Greek alphabet. The Lelantine War is the earliest documented war of the ancient Greek period and it was fought between the important poleis of Chalcis and Eretria over the fertile Lelantine plain of Euboea. Both cities seem to have suffered a decline as result of the long war, a mercantile class arose in the first half of the 7th century BC, shown by the introduction of coinage in about 680 BC
Ancient Greeks
–
The
Parthenon, a temple dedicated to
Athena, located on the
Acropolis in
Athens, is one of the most representative symbols of the culture and sophistication of the ancient Greeks.
Ancient Greeks
–
Dipylon Vase of the late Geometric period, or the beginning of the Archaic period,
c. 750 BC.
Ancient Greeks
–
Political geography of ancient Greece in the Archaic and Classical periods
4.
Life
–
Various forms of life exist, such as plants, animals, fungi, protists, archaea, and bacteria. The criteria can at times be ambiguous and may or may not define viruses, viroids, biology is the primary science concerned with the study of life, although many other sciences are involved. The definition of life is controversial, the current definition is that organisms maintain homeostasis, are composed of cells, undergo metabolism, can grow, adapt to their environment, respond to stimuli, and reproduce. However, many other definitions have been proposed, and there are some borderline cases. Modern definitions are more complex, with input from a diversity of scientific disciplines, biophysicists have proposed many definitions based on chemical systems, there are also some living systems theories, such as the Gaia hypothesis, the idea that the Earth itself is alive. Another theory is that life is the property of systems, and yet another is elaborated in complex systems biology. Abiogenesis describes the process of life arising from non-living matter. Properties common to all organisms include the need for certain chemical elements to sustain biochemical functions. Life on Earth first appeared as early as 4.28 billion years ago, soon after ocean formation 4.41 billion years ago, Earths current life may have descended from an RNA world, although RNA-based life may not have been the first. The mechanism by which began on Earth is unknown, though many hypotheses have been formulated and are often based on the Miller–Urey experiment. The earliest known forms are microfossils of bacteria. In July 2016, scientists reported identifying a set of 355 genes believed to be present in the last universal ancestor of all living organisms. Since its primordial beginnings, life on Earth has changed its environment on a time scale. To survive in most ecosystems, life must often adapt to a range of conditions. Some microorganisms, called extremophiles, thrive in physically or geochemically extreme environments that are detrimental to most other life on Earth, Aristotle was the first person to classify organisms. Later, Carl Linnaeus introduced his system of nomenclature for the classification of species. Eventually new groups and categories of life were discovered, such as cells and microorganisms, cells are sometimes considered the smallest units and building blocks of life. There are two kinds of cells, prokaryotic and eukaryotic, both of which consist of cytoplasm enclosed within a membrane and contain many such as proteins
Life
–
Life (
Biota / Vitae / Eobionti)
Life
–
This article is one of a series on:
Life
–
Plant growth in the
Hoh Rainforest
Life
–
Herds of zebra and impala gathering on the
Maasai Mara plain
5.
Organisms
–
In biology, an organism is any contiguous living system, such as an animal, plant, fungus, protist, archaeon, or bacterium. All known types of organisms are capable of some degree of response to stimuli, reproduction, growth and development and homeostasis. An organism consists of one or more cells, when it has one cell it is known as an organism. Most unicellular organisms are of microscopic scale and are thus described as microorganisms. Humans are multicellular organisms composed of trillions of cells grouped into specialized tissues. An organism may be either a prokaryote or a eukaryote, prokaryotes are represented by two separate domains—bacteria and archaea. Eukaryotic organisms are characterized by the presence of a cell nucleus. Fungi, animals and plants are examples of kingdoms of organisms within the eukaryotes, estimates on the number of Earths current species range from 10 million to 14 million, of which only about 1.2 million have been documented. More than 99% of all species, amounting to five billion species. In 2016, a set of 355 genes from the last universal ancestor of all living organisms living was identified. The term organism first appeared in the English language in 1703 and it is directly related to the term organization. There is a tradition of defining organisms as self-organizing beings. An organism may be defined as an assembly of molecules functioning as a more or less stable whole that exhibits the properties of life. Dictionary definitions can be broad, using such as any living structure, such as a plant, animal, fungus or bacterium, capable of growth. Many definitions exclude viruses and possible man-made non-organic life forms, as viruses are dependent on the machinery of a host cell for reproduction. A superorganism is an organism consisting of individuals working together as a single functional or social unit. There has been controversy about the best way to define the organism, several contributions are responses to the suggestion that the category of organism may well not be adequate in biology. Viruses are not typically considered to be organisms because they are incapable of autonomous reproduction and this controversy is problematic because some cellular organisms are also incapable of independent survival and live as obligatory intracellular parasites
Organisms
–
These
Escherichia coli cells provide an example of a
prokaryotic microorganism.
Organisms
–
A
polypore mushroom has a
parasitic relationship with its
host.
Organisms
–
An
ericoid mycorrhizal fungus
Organisms
6.
Unicellular
–
A unicellular organism, also known as a single-celled organism, is an organism that consists of only one cell, unlike a multicellular organism that consists of more than one cell. Historically, simple unicellular organisms have been referred to as monads, though this term is used more specifically to describe organisms of the genus Monas. The main groups of organisms are bacteria, archaea, protozoa, unicellular algae. Unicellular organisms fall into two categories, prokaryotic organisms and eukaryotic organisms. Unicellular organisms are thought to be the oldest form of life, prokaryotes, most Protista, and some fungi are unicellular. Although some of these live in colonies, they dont exhibit specialization. These organisms live together, and each cell in the colony is the same, however, each individual cell must carry out all life processes to survive. In contrast, even the simplest multicellular organisms have cells that depend on each other to survive, most multicellular organisms have a unicellular life-cycle stage. Gametes, for example, are reproductive unicells for multicellular organisms, additionally, multicellularity appears to have evolved independently many times in the history of life. Some organisms are partially uni- and multicellular, like Dictyostelium discoideum, additionally, unicellular organisms can be multinucleate, like Myxogastria and Plasmodium. Candidatus Magnetoglobus multicellular, related to Deltaproteobacteria, is a multicellular prokaryote and it is neither unicellular, nor a colony. Primitive cells, often referred to as protocells, are the precursors to todays unicellular organisms, the RNA world hypothesis assumes that RNA molecules could form in abiotic conditions, which would require nucleic acids and ribose to be present. Theoretical and experimental findings show that nucleic acids and sugars could have been synthesized in early prebiotic conditions, compartmentalization was necessary for chemical reactions to be more likely as well as to differentiate reactions with the external environment. For example, an early RNA replicator ribozyme may have replicated other replicator ribozymes of different RNA sequences if not kept separate, when amphiphiles like lipids are placed in water, the hydrophobic tails aggregate to form micelles and vesicles, with the hydrophilic ends facing outwards. Primitive cells likely used self-assembling fatty-acid vesicles to separate chemical reactions, because of their simplicity and ability to self-assemble in water, its likely that these simple membranes predated other forms of early biological molecules. Prokaryotes lack membrane-bound organelles, such as mitochondria or a nucleus, instead, most prokaryotes have an irregular region that contains DNA, known as the nucleoid. Most prokaryotes have a single, circular chromosome, which is in contrast to eukaryotes, nutritionally, prokaryotes have the ability to utilize a wide range of organic and inorganic material for use in metabolism, including sulfur, cellulose, ammonia, or nitrite. Prokaryotes as a whole are ubiquitous in the environment and exist in extreme environments as well, bacteria are one of the world’s oldest forms of life, and are found virtually everywhere in nature
Unicellular
–
Valonia ventricosa, a species of
algae with a diameter that ranges typically from 1 to 4 centimetres (0.39 to 1.57 in) is among the largest unicellular species
7.
Multicellular
–
Multicellular organisms are organisms that consist of more than one cell, in contrast to unicellular organisms. Multicellular organisms arise in different ways, for example by cell division or by aggregation of many single cells. Colonial organisms are the result of identical individuals joining together to form a colony. Multicellularity has evolved independently at least 46 times, including in some prokaryotes, like cyanobacteria, myxobacteria, actinomycetes, however, complex multicellular organisms evolved only in six eukaryotic groups, animals, fungi, brown algae, red algae, green algae, and land plants. It evolved repeatedly for Chloroplastida, once or twice for animals, once for brown algae, the first evidence of multicellularity is from cyanobacteria-like organisms that lived 3–3.5 billion years ago. To reproduce, true multicellular organisms must solve the problem of regenerating a whole organism from germ cells, animals have evolved a considerable diversity of cell types in a multicellular body, compared with 10–20 in plants and fungi. Loss of multicellularity occurred in some groups, fungi are predominantly multicellular, though early diverging lineages are largely unicellular and there have been numerous reversions to unicellularity across fungi. It may also have occurred in some red algae, but it is possible that they are primitively unicellular), loss of multicellularity is also considered probable in some green algae. In other groups, generally parasites, a reduction of multicellularity occurred, multicellular organisms, especially long-living animals, face the challenge of cancer, which occurs when cells fail to regulate their growth within the normal program of development. Changes in tissue morphology can be observed during this process, cancer in animals has often been described as a loss of multicellularity. There is a discussion about the possibility of existence of cancer in other organisms or even in protozoa. For example, plant galls have been characterized as tumors but some argue that plants do not develop cancer. In some multicellular groups, which are called Weismannists, a separation between a sterile somatic cell line and a cell line evolved. However, Weismannist development is relatively rare, as part of species have the capacity for somatic embryogenesis. One hypothesis for the origin of multicellularity is that a group of function-specific cells aggregated into a mass called a grex. This is essentially what slime molds do, another hypothesis is that a primitive cell underwent nucleus division, thereby becoming a coenocyte. A membrane would then form around each nucleus, thereby resulting in a group of connected cells in one organism and this is what plant and animal embryos do as well as colonial choanoflagellates. Because the first multicellular organisms were simple, soft organisms lacking bone, shell or other body parts
Multicellular
–
In this image, a
wild-type Caenorhabditis elegans is stained to highlight the nuclei of its cells.
8.
Virology
–
Virology is the study of viruses – submicroscopic, parasitic particles of genetic material contained in a protein coat – and virus-like agents. Virology is considered to be a subfield of microbiology or of medicine, a major branch of virology is virus classification. Viruses can be classified according to the host cell they infect, animal viruses, plant viruses, fungal viruses, another classification uses the geometrical shape of their capsid or the viruss structure. Viruses range in size from about 30 nm to about 450 nm, the shape and structure of viruses has been studied by electron microscopy, NMR spectroscopy, and X-ray crystallography. The latest report by the International Committee on Taxonomy of Viruses lists 5450 viruses, virologists also study subviral particles, infectious entities notably smaller and simpler than viruses, viroids, satellites, and prions. Taxa in virology are not necessarily monophyletic, as the relationships of the various virus groups remain unclear. Viruses arose from mobile genetic elements of cells that became encapsulated in protein capsids, acquired the ability to free from the host cell. Of particular interest here is mimivirus, a giant virus that infects amoebae, is it a simplified version of a parasitic prokaryote, or did it originate as a simpler virus that acquired genes from its host. The evolution of viruses, which occurs in concert with the evolution of their hosts, is studied in the field of viral evolution. While viruses reproduce and evolve, they do not engage in metabolism, do not move, the often-debated question of whether they are alive or not is a matter of definition that does not affect the biological reality of viruses. Herpes simplex causes cold sores and genital herpes and is under investigation as a factor in Alzheimers. Some viruses, known as oncoviruses, contribute to the development of forms of cancer. The best studied example is the association between Human papillomavirus and cervical cancer, almost all cases of cancer are caused by certain strains of this sexually transmitted virus. Another example is the association of infection with hepatitis B and hepatitis C viruses, the study of the manner in which viruses cause disease is viral pathogenesis. The degree to which a virus disease is its virulence. When the immune system of a vertebrate encounters a virus, it may produce specific antibodies which bind to the virus, antibody presence in blood serum is often used to determine whether a person has been exposed to a given virus in the past, with tests such as ELISA. Vaccinations protect against viral diseases, in part, by eliciting the production of antibodies, monoclonal antibodies, specific to the virus, are also used for detection, as in fluorescence microscopy. This mechanism is jump-started by certain vaccinations, RNA interference, an important cellular mechanism found in plants, animals and many other eukaryotes, most likely evolved as a defense against viruses
Virology
–
Dmitri Ivanovsky
9.
Mycology
–
A biologist specializing in mycology is called a mycologist. From mycology arose the field of phytopathology, the study of plant diseases, historically, mycology was a branch of botany because, although fungi are evolutionarily more closely related to animals than to plants, this was not recognized until a few decades ago. Pioneer mycologists included Elias Magnus Fries, Christian Hendrik Persoon, Anton de Bary, many fungi produce toxins, antibiotics, and other secondary metabolites. For example, the cosmopolitan genus Fusarium and their toxins associated with outbreaks of alimentary toxic aleukia in humans were extensively studied by Abraham Joffe. Fungi are fundamental for life on earth in their roles as symbionts, e. g. in the form of mycorrhizae, insect symbionts, and lichens. Many fungi are able to break down complex organic biomolecules such as lignin, the more durable component of wood, and pollutants such as xenobiotics, petroleum, by decomposing these molecules, fungi play a critical role in the global carbon cycle. Fungi and other organisms traditionally recognized as fungi, such as oomycetes and myxomycetes, often are economically and socially important, apart from pathogenic fungi, many fungal species are very important in controlling the plant diseases caused by different pathogens. Field meetings to find interesting species of fungi are known as forays, after the first such meeting organized by the Woolhope Naturalists Field Club in 1868, some fungi can cause disease in humans or other organisms. The study of fungi is referred to as medical mycology. It is presumed that humans started collecting mushrooms as food in prehistoric times, mushrooms were first written about in the works of Euripides. The Greek philosopher Theophrastos of Eressos was perhaps the first to try to classify plants. It was later Pliny the Elder, who wrote about truffles in his encyclopedia Naturalis historia, the word mycology comes from the Greek, μύκης, meaning fungus and the suffix -λογία, meaning study. The Middle Ages saw little advancement in the body of knowledge about fungi, rather, the invention of the printing press allowed some authors to disseminate superstitions and misconceptions about the fungi that had been perpetuated by the classical authors. The start of the age of mycology begins with Pier Antonio Michelis 1737 publication of Nova plantarum genera. Published in Florence, this work laid the foundations for the systematic classification of grasses, mosses. The term mycology and the complementary mycologist were first used in 1836 by M. J. Berkeley, for centuries, certain mushrooms have been documented as a folk medicine in China, Japan, and Russia. Certain mushrooms, especially polypores like reishi were thought to be able to benefit a variety of health ailments. Medicinal mushroom research in the United States is currently active, with studies taking place at City of Hope National Medical Center, current research focuses on mushrooms that may have hypoglycemic activity, anti-cancer activity, anti-pathogenic activity, and immune system-enhancing activity
Mycology
–
Mushrooms are a kind of fungal reproductive structure
10.
Parasitology
–
Parasitology is the study of parasites, their hosts, and the relationship between them. As a biological discipline, the scope of parasitology is not determined by the organism or environment in question, much research in parasitology falls somewhere between two or more of these definitions. In general, the study of prokaryotes falls under the field of bacteriology rather than parasitology and it is also concerned with the various methods of their diagnosis, treatment and finally their prevention & control. A parasite is an organism that live on or within another organism called the host and these include organisms such as, Plasmodium spp. the protozoan parasite which causes malaria. The four species of malaria parasites infective to humans are Plasmodium falciparum, Plasmodium malariae, leishmania donovani, the unicellular organism which causes leishmaniasis Entamoeba and Giardia, which cause intestinal infections Multicellular organisms and intestinal worms such as Schistosoma spp. Wuchereria bancrofti, Necator americanus and Taenia spp, ectoparasites such as ticks, scabies and lice Medical parasitology can involve drug development, epidemiological studies and study of zoonoses. The study of parasites that cause losses in agriculture or aquaculture operations. Examples of species studied are, Lucilia sericata, a blowfly, the maggots hatch and burrow into the flesh, distressing the animal and causing economic loss to the farmer Otodectes cynotis, the cat ear mite, responsible for Canker. Gyrodactylus salaris, a parasite of salmon, which can wipe out populations which are not resistant. This is the study of structures of proteins from parasites, determination of parasitic protein structures may help to better understand how these proteins function differently from homologous proteins in humans. In addition, protein structures may inform the process of drug discovery, parasites exhibit an aggregated distribution among host individuals, thus the majority of parasites live in the minority of hosts. This feature forces parasitologists to use advanced biostatistical methodologies, parasites can provide information about host population ecology. In fisheries biology, for example, parasite communities can be used to distinguish distinct populations of the fish species co-inhabiting a region. Additionally, parasites possess a variety of specialized traits and life-history strategies that enable them to colonize hosts, understanding these aspects of parasite ecology, of interest in their own right, can illuminate parasite-avoidance strategies employed by hosts. Conservation biology is concerned with the protection and preservation of vulnerable species, the huge diversity between parasitic organisms creates a challenge for biologists who wish to describe and catalogue them. Parasitism Parasitologists Loker, E. & Hofkin, B
Parasitology
–
Adult
black fly (Simulium yahense) with (
Onchocerca volvulus) emerging from the insect's antenna. The parasite is responsible for the disease known as
river blindness in Africa. Sample was chemically fixed and critical point dried, then observed using conventional scanning electron microscopy. Magnified 100×.
Parasitology
–
The
Italian Francesco Redi, considered to be the father of modern parasitology, he was the first to recognize and correctly describe details of many important
parasites.
11.
Eukaryote
–
A eukaryote is any organism whose cells contain a nucleus and other organelles enclosed within membranes. Eukaryotes belong to the taxon Eukarya or Eukaryota, the presence of a nucleus gives eukaryotes their name, which comes from the Greek εὖ and κάρυον. Eukaryotic cells also contain other membrane-bound organelles such as mitochondria and the Golgi apparatus, in addition, plants and algae contain chloroplasts. Eukaryotic organisms may be unicellular or multicellular, only eukaryotes form multicellular organisms consisting of many kinds of tissue made up of different cell types. Eukaryotes can reproduce asexually through mitosis and sexually through meiosis and gamete fusion. In mitosis, one cell divides to produce two identical cells. In meiosis, DNA replication is followed by two rounds of division to produce four daughter cells each with half the number of chromosomes as the original parent cell. These act as sex cells resulting from genetic recombination during meiosis, the domain Eukaryota appears to be monophyletic, and so makes up one of the three domains of life. The two other domains, Bacteria and Archaea, are prokaryotes and have none of the above features, eukaryotes represent a tiny minority of all living things. However, due to their larger size, eukaryotes collective worldwide biomass is estimated at about equal to that of prokaryotes. Eukaryotes first developed approximately 1. 6–2.1 billion years ago, in 1905 and 1910, the Russian biologist Konstantin Mereschkowsky argued three things about the origin of nucleated cells. Firstly, plastids were reduced cyanobacteria in a symbiosis with a non-photosynthetic host, secondly, the host had earlier in evolution formed by symbiosis between an amoeba-like host and a bacteria-like cell that formed the nucleus. Thirdly, plants inherited photosynthesis from cyanobacteria, the split between the prokaryotes and eukaryotes was introduced in the 1960s. The concept of the eukaryote has been attributed to the French biologist Edouard Chatton, the terms prokaryote and eukaryote were more definitively reintroduced by the Canadian microbiologist Roger Stanier and the Dutch-American microbiologist C. B. van Niel in 1962. In his 1938 work Titres et Travaux Scientifiques, Chatton had proposed the two terms, calling the bacteria prokaryotes and organisms with nuclei in their cells eukaryotes. However he mentioned this in one paragraph, and the idea was effectively ignored until Chattons statement was rediscovered by Stanier. In 1967, Lynn Margulis provided microbiological evidence for endosymbiosis as the origin of chloroplasts and mitochondria in cells in her paper. In the 1970s, Carl Woese explored microbial phylogenetics, studying variations in 16S ribosomal RNA and this helped to uncover the origin of the eukaryotes and the symbiogenesis of two important eukaryote organelles, mitochondria and chloroplasts
Eukaryote
–
Had'n
Eukaryote
–
Longitudinal section through the flagellum of
Chlamydomonas reinhardtii
12.
Organelles
–
In cell biology, an organelle is a specialized subunit within a cell that has a specific function. Individual organelles are usually enclosed within their own lipid bilayers. The name organelle comes from the idea that these structures are to cells what an organ is to the body, organelles are identified by microscopy, and can also be purified by cell fractionation. There are many types of organelles, particularly in eukaryotic cells, while prokaryotes do not possess organelles per se, some do contain protein-based bacterial microcompartments, which are thought to act as primitive organelles. In biology organs are defined as confined functional units within an organism, the analogy of bodily organs to microscopic cellular substructures is obvious, as from even early works, authors of respective textbooks rarely elaborate on the distinction between the two. In the 1830s, Félix Dujardin refuted Ehrenberg theory which said that microorganims have the organs of multicellular animals. Credited as the first to use a diminutive of organ for cellular structures was German zoologist Karl August Möbius, under this definition, there would only be two broad classes of organelles, mitochondria plastids. Other organelles are also suggested to have endosymbiotic origins, but do not contain their own DNA, under the more restricted definition of membrane-bound structures, some parts of the cell do not qualify as organelles. Nevertheless, the use of organelle to refer to non-membrane bound structures such as ribosomes is common and this has led some texts to delineate between membrane-bound and non-membrane bound organelles. The larger organelles, such as the nucleus and vacuoles, are visible with the light microscope. They were among the first biological discoveries made after the invention of the microscope, not all eukaryotic cells have each of the organelles listed below. Exceptional organisms have cells that do not include some organelles that might otherwise be considered universal to eukaryotes, there are also occasional exceptions to the number of membranes surrounding organelles, listed in the tables below. In addition, the number of organelles of each type found in a given cell varies depending upon the function of that cell. This idea is supported in the Endosymbiotic theory, in the past, they were often viewed as having little internal organization, but slowly, details are emerging about prokaryotic internal structures. However, more recent research has revealed that at least some prokaryotes have microcompartments such as carboxysomes and these subcellular compartments are 100–200 nm in diameter and are enclosed by a shell of proteins. The function of a protein is correlated with the organelle in which it resides. CoRR Hypothesis Ejectosome Endosymbiotic theory Organelle biogenesis Membrane vesicle trafficking Host-pathogen interface Tree of Life project, Eukaryotes
Organelles
–
(A) Electron micrograph of
Halothiobacillus neapolitanus cells, arrows highlight
carboxysomes. (B) Image of intact carboxysomes isolated from H. neapolitanus. Scale bars are 100 nm.
Organelles
–
Nucleolus
13.
Fungi
–
A fungus is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from the other eukaryotic life kingdoms of plants, a characteristic that places fungi in a different kingdom from plants, bacteria and some protists, is chitin in their cell walls. Similar to animals, fungi are heterotrophs, they acquire their food by absorbing dissolved molecules, growth is their means of mobility, except for spores, which may travel through the air or water. Fungi are the principal decomposers in ecological systems and this fungal group is distinct from the structurally similar myxomycetes and oomycetes. The discipline of biology devoted to the study of fungi is known as mycology, in the past, mycology was regarded as a branch of botany, although it is now known fungi are genetically more closely related to animals than to plants. Abundant worldwide, most fungi are inconspicuous because of the size of their structures. Fungi include symbionts of plants, animals, or other fungi and they may become noticeable when fruiting, either as mushrooms or as molds. Fungi perform a role in the decomposition of organic matter and have fundamental roles in nutrient cycling. Since the 1940s, fungi have been used for the production of antibiotics, Fungi are also used as biological pesticides to control weeds, plant diseases and insect pests. Many species produce bioactive compounds called mycotoxins, such as alkaloids and polyketides, the fruiting structures of a few species contain psychotropic compounds and are consumed recreationally or in traditional spiritual ceremonies. Fungi can break down manufactured materials and buildings, and become significant pathogens of humans, losses of crops due to fungal diseases or food spoilage can have a large impact on human food supplies and local economies. The fungus kingdom encompasses a diversity of taxa with varied ecologies, life cycle strategies. However, little is known of the biodiversity of Kingdom Fungi. Advances in molecular genetics have opened the way for DNA analysis to be incorporated into taxonomy, phylogenetic studies published in the last decade have helped reshape the classification within Kingdom Fungi, which is divided into one subkingdom, seven phyla, and ten subphyla. The English word fungus is directly adopted from the Latin fungus, used in the writings of Horace, a group of all the fungi present in a particular area or geographic region is known as mycobiota, e. g. the mycobiota of Ireland. Like plants, fungi grow in soil and, in the case of mushrooms, form conspicuous fruit bodies. The fungi are now considered a kingdom, distinct from both plants and animals, from which they appear to have diverged around one billion years ago. Fungi have membrane-bound cytoplasmic organelles such as mitochondria, sterol-containing membranes and they have a characteristic range of soluble carbohydrates and storage compounds, including sugar alcohols, disaccharides, and polysaccharides
Fungi
Fungi
–
Omphalotus nidiformis, a bioluminescent mushroom
Fungi
–
Bracket fungi on a tree stump
Fungi
–
Two types of edible fungi
14.
Protists
–
Protist is an informal term for any eukaryotic organism that is not an animal, plant or fungus. The protists do not form a group, or clade. Besides their relatively simple levels of organization, protists do not necessarily have much in common, others use the term protist more broadly, to encompass both microbial eukaryotes and macroscopic organisms that do not fit into the other traditional kingdoms. In cladistic systems, there are no equivalents to the taxa Protista or Protoctista, in cladistic classification, the contents of Protista are distributed among various supergroups and Protista, Protoctista and Protozoa are considered obsolete. However, the term protist continues to be used informally as a term for eukaryotic microorganisms. For example, the phrase protist pathogen may be used to denote any disease-causing microbe which is not bacteria, virus, the term protista was first used by Ernst Haeckel in 1866. Some protists, sometimes called ambiregnal protists, have considered to be both protozoa and algae or fungi, and names for these have been published under either or both of the ICN and the ICZN. Conflicts, such as these – for example the dual-classification of Euglenids and Dinobryons and these traditional subdivisions, largely based on superficial commonalities, have been replaced by classifications based on phylogenetics. Molecular analyses in modern taxonomy have been used to redistribute former members of this group into diverse, however, the older terms are still used as informal names to describe the morphology and ecology of various protists. For example, the term protozoa is used to refer to species of protists that do not form filaments. Among the pioneers in the study of the protists, which were almost ignored by Linnaeus except for some genera were Leeuwenhoek, O. F. Müller, C. G. Ehrenberg, the first groups used to classify microscopic organism were the Animalcules and the Infusoria. In 1817, the German naturalist Georg August Goldfuss introduced the word Protozoa to refer to such as ciliates. After the cell theory of Schwann and Schleiden, this group was modified in 1848 by Carl von Siebold to include only animal-like unicellular organisms, such as foraminifera and amoebae. He defined the Protoctista as a kingdom of nature, in addition to the then-traditional kingdoms of plants. The kingdom of minerals was later removed from taxonomy in 1866 by Ernst Haeckel, leaving plants, animals, in 1938, Herbert Copeland resurrected Hoggs label, arguing that Haeckels term Protista included anucleated microbes such as bacteria, which the term Protoctista did not. In contrast, Copelands term included nucleated eukaryotes such as diatoms, green algae and this classification was the basis for Whittakers later definition of Fungi, Animalia, Plantae and Protista as the four kingdoms of life. The kingdom Protista was later modified to separate prokaryotes into the kingdom of Monera. Many systematists today do not treat Protista as a formal taxon, some systematists judge paraphyletic taxa acceptable, and use Protista in this sense as a formal taxon
Protists
–
Protist Temporal range:
Neoproterozoic – Recent
15.
Prokaryote
–
A prokaryote is a unicellular organism that lacks a membrane-bound nucleus, mitochondria, or any other membrane-bound organelle. The word prokaryote comes from the Greek πρό before and καρυόν nut or kernel, prokaryotes can be divided into two domains, Archaea and bacteria. In contrast, species with nuclei and organelles are placed in the domain Eukaryota, in the prokaryotes, all the intracellular water-soluble components are located together in the cytoplasm enclosed by the cell membrane, rather than in separate cellular compartments. Bacteria, however, do possess protein-based bacterial microcompartments, which are thought to act as primitive organelles enclosed in protein shells, some prokaryotes, such as cyanobacteria may form large colonies. Others, such as myxobacteria, have multicellular stages in their life cycles, molecular studies have provided insight into the evolution and interrelationships of the three domains of biological species. Eukaryotes are organisms, including humans, whose cells have a well defined membrane-bound nucleus, the division between prokaryotes and eukaryotes reflects the existence of two very different levels of cellular organization. Distinctive types of prokaryotes include extremophiles and methanogens, these are common in extreme environments. Prokaryotes have a cytoskeleton, albeit more primitive than that of the eukaryotes. At least some also contain intracellular structures that can be seen as primitive organelles. Membranous organelles are known in some groups of prokaryotes, such as vacuoles or membrane systems devoted to special metabolic properties, in addition, some species also contain carbohydrate-enclosed microcompartments, which have distinct physiological roles. Most prokaryotes are between 1 µm and 10 µm, but they can vary in size from 0.2 µm to 750 µm, Bacteria and archaea reproduce through asexual reproduction, usually by binary fission. DNA transfer between prokaryotic cells occurs in bacteria and archaea, although it has mainly studied in bacteria. In bacteria, gene transfer occurs by three processes and these are bacterial virus -mediated transduction, plasmid-mediated conjugation, and natural transformation. Transduction of bacterial genes by bacteriophage appears to reflect an occasional error during intracellular assembly of virus particles, the transfer of bacterial DNA is under the control of the bacteriophage’s genes rather than bacterial genes. Conjugation in the well-studied E. coli system is controlled by plasmid genes, infrequently during this process, a plasmid may integrate into the host bacterial chromosome, and subsequently transfer part of the host bacterial DNA to another bacterium. Plasmid mediated transfer of host bacterial DNA also appears to be a process rather than a bacterial adaptation. Natural bacterial transformation involves the transfer of DNA from one bacterium to another through the intervening medium, for a bacterium to bind, take up and recombine donor DNA into its own chromosome, it must first enter a special physiological state called competence. About 40 genes are required in Bacillus subtilis for the development of competence, the length of DNA transferred during B. subtilis transformation can be as much as a third to the whole chromosome
Prokaryote
–
Cell structure of a
bacterium, a member of one of the two domains of prokaryotic life
16.
Eubacteria
–
Bacteria constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a number of shapes, ranging from spheres to rods, Bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, Bacteria also live in symbiotic and parasitic relationships with plants and animals. Most bacteria have not been characterised, and only half of the bacterial phyla have species that can be grown in the laboratory. The study of bacteria is known as bacteriology, a branch of microbiology, There are typically 40 million bacterial cells in a gram of soil and a million bacterial cells in a millilitre of fresh water. There are approximately 5×1030 bacteria on Earth, forming a biomass which exceeds that of all plants, Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of bodies and bacteria are responsible for the putrefaction stage in this process. In March 2013, data reported by researchers in October 2012, was published and it was suggested that bacteria thrive in the Mariana Trench, which with a depth of up to 11 kilometres is the deepest known part of the oceans. Other researchers reported related studies that microbes thrive inside rocks up to 580 metres below the sea floor under 2.6 kilometres of ocean off the coast of the northwestern United States. According to one of the researchers, You can find microbes everywhere—theyre extremely adaptable to conditions, the vast majority of the bacteria in the body are rendered harmless by the protective effects of the immune system, though many are beneficial particularly in the gut flora. However several species of bacteria are pathogenic and cause diseases, including cholera, syphilis, anthrax, leprosy. The most common fatal diseases are respiratory infections, with tuberculosis alone killing about 2 million people per year. In developed countries, antibiotics are used to treat infections and are also used in farming, making antibiotic resistance a growing problem. Once regarded as constituting the class Schizomycetes, bacteria are now classified as prokaryotes. Unlike cells of animals and other eukaryotes, bacterial cells do not contain a nucleus and these evolutionary domains are called Bacteria and Archaea. The ancestors of modern bacteria were unicellular microorganisms that were the first forms of life to appear on Earth, for about 3 billion years, most organisms were microscopic, and bacteria and archaea were the dominant forms of life. In 2008, fossils of macroorganisms were discovered and named as the Francevillian biota, however, gene sequences can be used to reconstruct the bacterial phylogeny, and these studies indicate that bacteria diverged first from the archaeal/eukaryotic lineage. Bacteria were also involved in the second great evolutionary divergence, that of the archaea, here, eukaryotes resulted from the entering of ancient bacteria into endosymbiotic associations with the ancestors of eukaryotic cells, which were themselves possibly related to the Archaea
Eubacteria
–
Had'n
Eubacteria
–
A
biofilm of thermophilic bacteria in the outflow of
Mickey Hot Springs,
Oregon, approximately 20 mm thick.
Eubacteria
–
Helicobacter pylori electron micrograph, showing multiple flagella on the cell surface
Eubacteria
–
Bacillus anthracis (stained purple) growing in
cerebrospinal fluid
17.
Archaebacteria
–
The Archaea constitute a domain and kingdom of single-celled microorganisms. These microbes are prokaryotes, meaning that they have no cell nucleus or any other membrane-bound organelles in their cells, Archaea were initially classified as bacteria, receiving the name archaebacteria, but this classification is outdated. Archaeal cells have unique properties separating them from the two domains of life, Bacteria and Eukaryota. The Archaea are further divided into multiple recognized phyla, classification is difficult because the majority have not been isolated in the laboratory and have only been detected by analysis of their nucleic acids in samples from their environment. Archaea and bacteria are generally similar in size and shape, although a few archaea have very strange shapes, such as the flat, other aspects of archaeal biochemistry are unique, such as their reliance on ether lipids in their cell membranes, including archaeols. Archaea use more energy sources than eukaryotes, these range from organic compounds, such as sugars, to ammonia, metal ions or even hydrogen gas. Salt-tolerant archaea use sunlight as a source, and other species of archaea fix carbon, however, unlike plants and cyanobacteria. Archaea reproduce asexually by fission, fragmentation, or budding, unlike bacteria and eukaryotes. They are also found in the colon, oral cavity. Archaea are particularly numerous in the oceans, and the archaea in plankton may be one of the most abundant groups of organisms on the planet, Archaea are a major part of Earths life and may play roles in both the carbon cycle and the nitrogen cycle. No clear examples of archaeal pathogens or parasites are known, one example is the methanogens that inhabit human and ruminant guts, where their vast numbers aid digestion. Methanogens are also used in production and sewage treatment, and enzymes from extremophile archaea that can endure high temperatures. For much of the 20th century, prokaryotes were regarded as a group of organisms and classified based on their biochemistry, morphology. For example, microbiologists tried to classify based on the structures of their cell walls, their shapes. In 1965, Emile Zuckerkandl and Linus Pauling proposed instead using the sequences of the genes in different prokaryotes to work out how they are related to each other and this approach, known as phylogenetics, is the main method used today. Archaea were first classified as a group of prokaryotes in 1977 by Carl Woese. These two groups were named the Archaebacteria and Eubacteria and treated as kingdoms or subkingdoms, which Woese. Woese argued that group of prokaryotes is a fundamentally different sort of life
Archaebacteria
–
Had'n
Archaebacteria
–
Archaea were first found in extreme environments, such as volcanic
hot springs. Pictured here is
Grand Prismatic Spring of
Yellowstone National Park.
Archaebacteria
–
The
ARMAN are a new group of archaea recently discovered in
acid mine drainage.
Archaebacteria
–
Archaea that grow in the hot water of the Morning Glory
Hot Spring in
Yellowstone National Park produce a bright colour
18.
Nucleic acid
–
Nucleic acids are biopolymers, or large biomolecules, essential to all known forms of life. They are composed of monomers, which are made of three components, a 5-carbon sugar, a phosphate group, and a nitrogenous base. If the sugar is a simple ribose, the polymer is RNA, if the sugar is derived from ribose as deoxyribose, Nucleic acids are arguably the most important of all biomolecules. They are found in abundance in all living things, where they function to create and encode, the encoded information is contained and conveyed via the nucleic acid sequence, which provides the ladder-step ordering of nucleotides within the molecules of RNA and DNA. Using amino acids and the known as protein synthesis, the specific sequencing in DNA of these nucleobase-pairs enables storing and transmitting coded instructions as genes. In RNA, base-pair sequencing provides for manufacturing new proteins that determine the frames and parts, Nucleic acids were discovered by Friedrich Miescher in 1869. In 1889 Richard Altmann discovered that nuclein has acidic properties, and it became called nucleic acid In 1938 Astbury, in 1953 Watson and Crick determined the structure of DNA. The term nucleic acid is the name for DNA and RNA, members of a family of biopolymers. Nucleic acids were named for their initial discovery within the nucleus, all living cells contain both DNA and RNA, while viruses contain either DNA or RNA, but usually not both. The basic component of nucleic acids is the nucleotide, each of which contains a pentose sugar, a phosphate group. Nucleic acids are generated within the laboratory, through the use of enzymes. The chemical methods also enable the generation of altered nucleic acids that are not found in nature, Nucleic acids are generally very large molecules. Indeed, DNA molecules are probably the largest individual molecules known, well-studied biological nucleic acid molecules range in size from 21 nucleotides to large chromosomes. In most cases, naturally occurring DNA molecules are double-stranded and RNA molecules are single-stranded, Nucleic acids are linear polymers of nucleotides. Each nucleotide consists of three components, a purine or pyrimidine nucleobase, a sugar, and a phosphate group. The substructure consisting of a nucleobase plus sugar is termed a nucleoside, Nucleic acid types differ in the structure of the sugar in their nucleotides–DNA contains 2-deoxyribose while RNA contains ribose. Also, the found in the two nucleic acid types are different, adenine, cytosine, and guanine are found in both RNA and DNA, while thymine occurs in DNA and uracil occurs in RNA. The sugars and phosphates in nucleic acids are connected to other in an alternating chain through phosphodiester linkages
Nucleic acid
–
The
Swiss scientist Friedrich Miescher discovered nucleic acids (
DNA) in 1869. Later, he raised the idea that they could be involved in
heredity.
Nucleic acid
–
A comparison of the two principal nucleic acids: RNA (left) and DNA (right), showing the helices and
nucleobases each employs.
19.
Marcus Terentius Varro
–
Marcus Terentius Varro was an ancient Roman scholar and writer. He is sometimes called Varro Reatinus to distinguish him from his younger contemporary Varro Atacinus, politically, he supported Pompey, reaching the office of praetor, after having been tribune of the people, quaestor and curule aedile. He was one of the commission of twenty that carried out the great scheme of Caesar for the resettlement of Capua. During the civil war he commanded one of Pompeys armies in the Ilerda campaign and he escaped the penalties of being on the losing side in the civil war through two pardons granted by Julius Caesar, before and after the Battle of Pharsalus. As the Republic gave way to Empire, Varro gained the favour of Augustus, under whose protection he found the security and quiet to devote himself to study, Varro studied under the Roman philologist Lucius Aelius Stilo, and later at Athens under the Academic philosopher Antiochus of Ascalon. Varro proved to be a productive writer and turned out more than 74 Latin works on a variety of topics. Among his many works, two stand out for historians, Nine Books of Disciplines and his compilation of the Varronian chronology and his Nine Books of Disciplines became a model for later encyclopedists, especially Pliny the Elder. The most noteworthy portion of the Nine Books of Disciplines is its use of the arts as organizing principles. Varro decided to focus on identifying nine of these arts, grammar, rhetoric, logic, arithmetic, geometry, astronomy, musical theory, medicine, using Varros list, subsequent writers defined the seven classical liberal arts of the medieval schools. The compilation of the Varronian chronology was an attempt to determine an exact timeline of Roman history up to his time. It is based on the sequence of the consuls of the Roman Republic — supplemented. His only complete work extant, Rerum rusticarum libri tres, has described as the well digested system of an experienced and successful farmer who has seen. One noteworthy aspect of the work is his anticipation of microbiology and epidemiology, Varro warned his contemporaries to avoid swamps and marshland, since in such areas. There are bred certain minute creatures which cannot be seen by the eyes, but which float in the air and enter the body through the mouth and nose and cause serious diseases. 199–242, in the collection of Wilmanns, pp. 170–223, and in that of Funaioli, pp. 179–371. G. Kent Livius. org, Varronian chronology thelatinlibrary. com, Latin works of Varro
Marcus Terentius Varro
–
Plan of the birdhouse at Casinum designed and built by Varro
Marcus Terentius Varro
–
Fasti Antiates Maiores, an inscription containing the
Roman calendar. This calendar predates the Julian reform of the calendar; it contains the months
Quintilis and
Sextilis, and allows for the insertion of an
intercalary month
20.
Robert Hooke
–
Robert Hooke FRS was an English natural philosopher, architect and polymath. Allan Chapman has characterised him as Englands Leonardo, Robert Gunthers Early Science in Oxford, a history of science in Oxford during the Protectorate, Restoration and Age of Enlightenment, devotes five of its fourteen volumes to Hooke. Hooke studied at Wadham College, Oxford during the Protectorate where he became one of a tightly knit group of ardent Royalists led by John Wilkins. Here he was employed as an assistant to Thomas Willis and to Robert Boyle and he built some of the earliest Gregorian telescopes and observed the rotations of Mars and Jupiter. In 1665 he inspired the use of microscopes for scientific exploration with his book, based on his microscopic observations of fossils, Hooke was an early proponent of biological evolution. Much of Hookes scientific work was conducted in his capacity as curator of experiments of the Royal Society, much of what is known of Hookes early life comes from an autobiography that he commenced in 1696 but never completed. Richard Waller mentions it in his introduction to The Posthumous Works of Robert Hooke, the work of Waller, along with John Wards Lives of the Gresham Professors and John Aubreys Brief Lives, form the major near-contemporaneous biographical accounts of Hooke. Robert Hooke was born in 1635 in Freshwater on the Isle of Wight to John Hooke, Robert was the last of four children, two boys and two girls, and there was an age difference of seven years between him and the next youngest. Their father John was a Church of England priest, the curate of Freshwaters Church of All Saints, Robert Hooke was expected to succeed in his education and join the Church. John Hooke also was in charge of a school, and so was able to teach Robert. He was a Royalist and almost certainly a member of a group who went to pay their respects to Charles I when he escaped to the Isle of Wight, Robert, too, grew up to be a staunch monarchist. As a youth, Robert Hooke was fascinated by observation, mechanical works and he dismantled a brass clock and built a wooden replica that, by all accounts, worked well enough, and he learned to draw, making his own materials from coal, chalk and ruddle. Hooke quickly mastered Latin and Greek, made study of Hebrew. Here, too, he embarked on his study of mechanics. It appears that Hooke was one of a group of students whom Busby educated in parallel to the work of the school. Contemporary accounts say he was not much seen in the school, in 1653, Hooke secured a choristers place at Christ Church, Oxford. He was employed as an assistant to Dr Thomas Willis. There he met the natural philosopher Robert Boyle, and gained employment as his assistant from about 1655 to 1662, constructing, operating and he did not take his Master of Arts until 1662 or 1663
Robert Hooke
–
Modern portrait of Robert Hooke (Rita Greer 2004), based on descriptions by
Aubrey and
Waller; no contemporary depictions of Hooke are known to survive.
Robert Hooke
–
Memorial portrait of Robert Hooke at
Alum Bay,
Isle of Wight, his birthplace, by Rita Greer (2012).
Robert Hooke
–
Robert Boyle
Robert Hooke
–
Diagram of a
louse from Hooke's
Micrographia
21.
Athanasius Kircher
–
Athanasius Kircher, S. J. was a German Jesuit scholar and polymath who published around 40 major works, most notably in the fields of comparative religion, geology, and medicine. Kircher has been compared to fellow Jesuit Roger Boscovich and to Leonardo da Vinci for his enormous range of interests and he taught for more than forty years at the Roman College, where he set up a wunderkammer. A resurgence of interest in Kircher has occurred within the community in recent decades. Kircher claimed to have deciphered the writing of the ancient Egyptian language. He did, however, correctly establish the link between the ancient Egyptian and the Coptic languages, and some regard him as the founder of Egyptology. Kirchers work in geology included studies of volcanoes and fossils, Kircher also displayed a keen interest in technology and mechanical inventions, inventions attributed to him include a magnetic clock, various automatons and the first megaphone. The invention of the lantern is often misattributed to Kircher. A scientific star in his day, towards the end of his life he was eclipsed by the rationalism of René Descartes, in the late 20th century, however, the aesthetic qualities of his work again began to be appreciated. One modern scholar, Alan Cutler, described Kircher as a giant among seventeenth-century scholars, another scholar, Edward W. Schmidt, referred to Kircher as the last Renaissance man. Kircher was born on 2 May in either 1601 or 1602 in Geisa, Buchonia, near Fulda, currently Hesse, from his birthplace he took the epithets Bucho, Buchonius and Fuldensis which he sometimes added to his name. He attended the Jesuit College in Fulda from 1614 to 1618, the youngest of nine children, Kircher studied volcanoes owing to his passion for rocks and eruptions. He was taught Hebrew by a rabbi in addition to his studies at school and he studied philosophy and theology at Paderborn, but fled to Cologne in 1622 to escape advancing Protestant forces. On the journey, he escaped death after falling through the ice crossing the frozen Rhine — one of several occasions on which his life was endangered. Later, traveling to Heiligenstadt, he was caught and nearly hanged by a party of Protestant soldiers, from 1622 to 1624 Kircher was sent to begin his regency period in Koblenz as a teacher. He was ordained to the priesthood in 1628 and became professor of ethics and mathematics at the University of Würzburg, beginning in 1628, he also began to show an interest in Egyptian hieroglyphs. In 1631, while still at Würzburg, Kircher allegedly had a vision of a bright light. This was the year that Kircher published his first book, in 1633 he was called to Vienna by the emperor to succeed Kepler as Mathematician to the Habsburg court. On the intervention of Nicolas-Claude Fabri de Peiresc, the order was rescinded and he was sent instead to Rome to continue with his scholarly work, on the way, his ship was blown off course and he arrived in Rome before he knew of the changed decision
Athanasius Kircher
–
Portrait of Kircher at age 53 from Mundus Subterraneus (1664)
Athanasius Kircher
–
The
Coptic alphabet, from Prodromus coptus sive aegyptiacus.
Athanasius Kircher
–
Map of China, China Illustrata.
Athanasius Kircher
–
Kircher's model of the
Earth 's internal fires, from Mundus Subterraneus.
22.
Antonie van Leeuwenhoek
–
Antonie Philips van Leeuwenhoek was a Dutch businessman, scientist, and one of the notable representatives in the golden age of Dutch science and technology. A largely self-taught man in science, he is known as the Father of Microbiology. Van Leeuwenhoek is best known for his work in the field of microscopy. Raised in Delft, in the Dutch Republic, Van Leeuwenhoek worked as a draper in his youth and he made a name for himself in municipal politics, and eventually developed an interest in lensmaking. Using his handcrafted microscopes, he was the first to observe and describe microorganisms, most of the animalcules are now referred to as unicellular organisms, though he observed multicellular organisms in pond water. He was also the first to document microscopic observations of muscle fibers, bacteria, spermatozoa, Van Leeuwenhoek did not write any books, his discoveries came to light through correspondence with the Royal Society, which published his letters. Antonie van Leeuwenhoek was born in Delft, Dutch Republic, on 24 October 1632, on 4 November, he was baptized as Thonis. His father, Philips Antonisz van Leeuwenhoek, was a maker who died when Antonie was only five years old. His mother, Margaretha, came from a well-to-do brewers family, and remarried Jacob Jansz Molijn, Antonie had four older sisters, Margriet, Geertruyt, Neeltje, and Catharina. When he was ten years old his step-father died. He attended school in Warmond for a time before being sent to live in Benthuizen with his uncle. At the age of 16 he became an apprentice at a linen-drapers shop in Amsterdam owned by the Scot William Davidson. Van Leeuwenhoek left after six years, Van Leeuwenhoek married Barbara de Mey in July 1654, with whom he would have one surviving daughter, Maria. That same year he returned to Delft, where he would live and he opened a drapers shop, which he ran throughout the 1650s. His wife died in 1666, and in 1671, Van Leeuwenhoek remarried to Cornelia Swalmius with whom he had no children and his status in Delft had grown throughout the years. In 1660 he received a job as chamberlain for the Delft sheriffs assembly chamber in the City Hall. Van Leeuwenhoek was a contemporary of another famous Delft citizen, the painter Johannes Vermeer and it has been suggested that he is the man portrayed in two of Vermeers paintings of the late 1660s, The Astronomer and The Geographer. However, others argue that there appears to be little physical similarity, while running his drapers shop, Van Leeuwenhoek wanted to see the quality of the thread better than the then-current magnifying lenses available allowed
Antonie van Leeuwenhoek
–
Portrait of Antonie van Leeuwenhoek (1632–1723) by
Jan Verkolje
Antonie van Leeuwenhoek
–
William Davidson had appointed Van Leeuwenhoek in 1648 as his assistant. Van Leeuwenhoek left after six years. (Portrait by
Abraham van den Tempel, 1664)
Antonie van Leeuwenhoek
–
The Geographer by
Johannes Vermeer.
Antonie van Leeuwenhoek
–
Microscopic section through one-year-old
ash tree (Fraxinus) wood, drawing made by Van Leeuwenhoek.
23.
Microscope
–
A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy, microscopic means invisible to the eye unless aided by a microscope. There are many types of microscopes, the most common is the optical microscope, which uses light to image the sample. Other major types of microscopes are the microscope, the ultramicroscope. The earliest microscopes were single lens magnifying glasses with limited magnification which date at least as far back as the wide use of lenses in eyeglasses in the 13th century. Compound microscopes, which combine an objective lens with an eyepiece to view a real image, the actual inventor of the compound microscope is unknown although many claims have been made over the years. These include what may be a claim by the son of Zacharias Janssen that his father invented the microscope and telescope as early as 1590. Historians note the compound microscope did not appear in the Netherlands until the 1620s, giovanni Faber coined the name microscope for the compound microscope Galileo submitted to the Accademia dei Lincei in 1625. The first detailed account of the construction of living tissue based on the use of a microscope did not appear until 1644, in Giambattista Odiernas Locchio della mosca. It was not until the 1660s and 1670s that the microscope was used extensively for research in Italy, marcello Malpighi in Italy began the analysis of biological structures, beginning with the lungs. Robert Hookes Micrographia had an impact, largely because of its impressive illustrations. A significant contribution came from Antonie van Leeuwenhoek who achieved up to 300 times magnification using a single lens microscope. He sandwiched a very small glass ball lens between the holes in two metal plates riveted together, and with a needle attached to mount the specimen. Then, Van Leeuwenhoek re-discovered red blood cells and spermatozoa, on 9 October 1676, he reported the discovery of micro-organisms. The performance of light microscopy depends as much on how the sample is illuminated as on how it is observed, early instruments were limited until this principle was fully appreciated and developed, and until electric lamps were available as light sources. In 1893 August Köhler developed a key principle of sample illumination, Köhler illumination and this method of sample illumination produces even lighting and overcomes the limited contrast and resolution imposed by early techniques of sample illumination. In the early 20th century a significant alternative to light microscopy was developed, ernst Ruska started development of the first electron microscope in 1931 which was the transmission electron microscope. The transmission electron microscope works on the principle as an optical microscope but uses electrons in the place of light
Microscope
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Compound Microscope
Microscope
–
18th century microscopes from the
Musée des Arts et Métiers,
Paris
Microscope
–
Robert Hooke's microscope and other Instruments
Microscope
–
An ant as imaged using a
scanning electron microscope (SEM)
24.
Louis Pasteur
–
Louis Pasteur was a French biologist, microbiologist and chemist renowned for his discoveries of the principles of vaccination, microbial fermentation and pasteurization. He is remembered for his breakthroughs in the causes and prevention of diseases. He reduced mortality from puerperal fever, and created the first vaccines for rabies and his medical discoveries provided direct support for the germ theory of disease and its application in clinical medicine. He is best known to the public for his invention of the technique of treating milk and wine to stop bacterial contamination. He is regarded as one of the three founders of bacteriology, together with Ferdinand Cohn and Robert Koch, and is popularly known as the father of microbiology. Pasteur was responsible for disproving the doctrine of spontaneous generation and he performed experiments that showed that without contamination, microorganisms could not develop. Under the auspices of the French Academy of Sciences, he demonstrated that in sterilized and sealed flasks nothing ever developed, although Pasteur was not the first to propose the germ theory, his experiments indicated its correctness and convinced most of Europe that it was true. Today, he is regarded as one of the fathers of germ theory. Pasteur also made significant discoveries in chemistry, most notably on the basis for the asymmetry of certain crystals. Early in his career, his investigation of tartaric acid resulted in the first resolution of what is now called optical isomers and his work led the way to the current understanding of a fundamental principle in the structure of organic compounds. He was the director of the Pasteur Institute, established in 1887, till his death, although Pasteur made groundbreaking experiments, his reputation became associated with various controversies. Historical reassessment of his notebook revealed that he practiced deception to overcome his rivals, Louis Pasteur was born on December 27,1822, in Dole, Jura, France, to a Catholic family of a poor tanner. He was the child of Jean-Joseph Pasteur and Jeanne-Etiennette Roqui. The family moved to Marnoz in 1826 and then to Arbois in 1827, Pasteur entered primary school in 1831. He was a student in his early years, and not particularly academic. He drew many pastels and portraits of his parents, friends, Pasteur attended secondary school at the Collège dArbois. In October 1838, he left for Paris to join the Pension Barbet, in 1839, he entered the Collège Royal de Besançon to study philosophy and earned his Bachelor of Letters degree in 1840. He was appointed a tutor at the Besançon college while continuing a degree course with special mathematics
Louis Pasteur
–
Photograph by
Nadar
Louis Pasteur
–
The house in which Pasteur was born,
Dole
Louis Pasteur
–
Pasteur in 1857
Louis Pasteur
–
Pasteur experimenting in his laboratory.
25.
Robert Koch
–
Robert Heinrich Hermann Koch was a celebrated German physician and pioneering microbiologist. In addition to his studies on these diseases, Koch created and improved laboratory technologies and techniques in the field of microbiology. As a result of his research on tuberculosis, Koch received the Nobel Prize in Physiology or Medicine in 1905. Robert Koch was born in Clausthal, Hanover, Germany, on 11 December 1843, to Hermann Koch, Koch excelled in academics from an early age. Before entering school in 1848, he had taught himself how to read and he graduated from high school in 1862, having excelled in science and maths. At the age of 19, Koch entered the University of Göttingen, however, after three semesters, Koch decided to change his area of study to medicine, as he aspired to be a physician. During his fifth semester of school, Jacob Henle, an anatomist who had published a theory of contagion in 1840. In his sixth semester, Koch began to research at the Physiological Institute. This would eventually form the basis of his dissertation, in January 1866, Koch graduated from medical school, earning honors of the highest distinction. Several years after his graduation in 1866, he worked as a surgeon in the Franco-Prussian War, from 1880-1885, Koch held a position as government advisor with the Imperial Department of Health. Koch began conducting research on microorganisms in a laboratory connected to his patient examination room, koch’s early research in this laboratory yielded one of his major contributions to the field of microbiology, as he developed the technique of growing bacteria. Furthermore, he managed to isolate and grow selected pathogens in pure laboratory culture, from 1885 to 1890, he served as an administrator and professor at Berlin University. For this he accepted harsh conditions, the Prussian Ministry of Health insisted after the scandal with tuberculin, that any of Kochs inventions would unconditionally belong to the government and not compensated. Koch lost the right to apply for patent protection, in an attempt to grow bacteria, Koch began to use solid nutrients such as potato slices. Through these initial experiments, Koch observed individual colonies of identical and he found that potato slices were not suitable media for all organisms, and later began to use nutrient solutions with gelatin. Koch’s discovery of the agent of anthrax led to the formation of a generic set of postulates which can be used in the determination of the cause of most infectious diseases. The organism must be isolated from a host containing the disease, samples of the organism taken from pure culture must cause the same disease when inoculated into a healthy, susceptible animal in the laboratory. The organism must be isolated from the animal and must be identified as the same original organism first isolated from the originally diseased host
Robert Koch
–
Robert Koch
26.
Jainism
–
Jainism, traditionally known as Jain Dharma, is an ancient Indian religion belonging to the śramaṇa tradition. The central tenet is non-violence and respect all living beings. The three main principles of Jainism are ahimsa, anekantavada and aparigraha, followers of Jainism take five main vows, ahimsa, satya, asteya, brahmacharya and aparigraha. Jain monks and nuns observe these vows absolutely whereas householders observe them within their practical limitations, self-discipline and asceticism are thus major focuses of Jainism. The word Jain derives from the Sanskrit word jina, a human being who has conquered all inner passions like attachment, desire, anger, pride, greed, etc. is called Jina. Followers of the path practiced and preached by the jinas are known as Jains, Parasparopagraho Jivanam is the motto of Jainism. Jains trace their history through a succession of teachers and revivers of the Jain path known as Tirthankaras. In the current era, this started with Rishabhdeva and concluded with Mahavira, Jains believe that Jainism is eternal and while it may be forgotten, it will be revived from time to time. With 6-7 million followers, the majority of Jains reside in India, outside of India, some of the largest Jain communities are present in Canada, Europe, Kenya, the UK, Suriname, Fiji, and the United States. Contemporary Jainism is divided into two sects, Digambara and Śvētāmbara. Namokar Mantra is the most common and basic prayer in Jainism, major Jain festivals include Paryushana and Daslakshana, Mahavir Jayanti, and Diwali. The principle of ahimsa is the most fundamental and well-known aspect of Jainism, the everyday implementation of the principle of non-violence is more comprehensive than in other religions and is the hallmark for Jain identity. Jains believe in avoiding harm to others thoughts, speech. According to the Jain text, Purushartha Siddhyupaya, killing any living being out of passions is hiṃsā, Jains extend the practice of nonviolence and kindness not only towards other humans but towards all living beings. For this reason, vegetarianism is a hallmark of Jain identity, if there is violence against animals during the production of dairy products, veganism is encouraged. Jainism has an elaborate framework on types of life and includes life-forms that may be invisible. Therefore, after humans and animals, insects are the living being offered protection in Jain practice. For example, insects in the home are often escorted out instead of killed, Jainism teaches that intentional harm and the absence of compassion make an action more violent
Jainism
–
Sculpture depicting Ahimsa, the fundamental tenet of Jainism (Photo:
Ahinsa Sthal)
Jainism
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Mahāvīra employed anekānta extensively to explain Jain philosophical concepts (painting from
Rajasthan, ca. 1900)
Jainism
–
Image of
Rishabha, first
tīrthaṅkara of the present Avsarpini era (Photo - Kundalpur, Madhya Pradesh)
Jainism
–
Siddhas (the liberated beings), although they are formless, this is how they are depicted in Jain temples
27.
Jain scriptures
–
Jain literature comprises Jain Agamas and subsequent commentaries on them by various Jain asectics. Jain literature is divided between Digambara literature and Svetambara literature. Jains literature exists mainly in Jain Prakrit, Sanskrit, Marathi, Tamil, Rajasthani, Dhundari, Marwari, Hindi, Gujarati, Kannada, Malayalam, Tulu, the canonical texts of Jainism are called Agamas. These are said to be based on the discourse of the tirthankara and these discourses are termed as Śrutu Jnāna and comprises eleven angas and fourteen purvas. According to the Jains, the canonical literature originated from the first tirthankara Rishabhanatha, the Digambara sect believes that there were 26 Agam‑sutras. However, they were gradually lost starting from one hundred fifty years after Lord Mahavirs nirvana, hence, they do not recognize the existing Agam-sutras as their authentic scriptures. In Digambara tradition, two texts, three commentaries on main texts, and four Anuyogas consisting of more than 20 texts are followed. These scriptures were written by great Acharyas from 100 to 1000 AD using the original Agama Sutras as the basis for their work. K. Jain, The prathmanuyoga contains the history, the karananuyoga contains works on cosmology. The Shatkhandagama is also known as Maha‑kammapayadi‑pahuda or Maha‑karma‑prabhrut, two Acharyas, Pushpadanta and Bhutabali wrote it around 160 AD. The second Purva‑agama named Agraya‑niya was used as the basis for this text, Acharya Virasena wrote two commentary texts, known as Dhaval‑tika on the first five volumes and Maha‑dhaval‑tika on the sixth volume of this scripture, around 780 AD. Acharya Gunadhara wrote the Kasay-pahud on the basis of the fifth Purva‑agama named Jnana‑pravad, Acharya Virasena and his disciple, Jinasena, wrote a commentary text known as Jaya‑dhaval‑tika around 780 AD. It is based on the major Jain text, Dhavala written by the Acharya Bhutabali and Acharya Pushpadanta. It is also called Pancha Sangraha, a collection of five topics, That which is bound, i. e. the Soul, That which is bound to the soul, That which binds, The varieties of bondage, bhadrabahu is considered by the jains as last sutra-kevali. He wrote various books known as niyukti, which are commentaries on those scriptures and he also wrote Samhita, a book dealing with legal cases. Umaswati wrote Tattvarthadhigama-sutra which briefly describes all the basic tennets of Jainism, haribhadra wrote the Yogadṛṣṭisamuccaya, a key Jain text on Yoga which compares the Yoga systems of Buddhists, Hindus and Jains. Siddhasena Divakara, a contemporary of Vikramaditya, wrote Nyayavatra a work on pure logic, Hemachandra wrote the Yogaśāstra, a textbook on yoga and Adhatma Upanishad. His minor work Vitragastuti gives outlines of the Jaina doctrine in form of hymns and this was later detailed by Mallisena in his work Syadavadamanjari
Jain scriptures
–
Folio from a
Kalpasutra (Book of Sacred Precepts), c. 1450, from Collection of
LACMA.
Jain scriptures
–
Acharya Tulsi and
Acharya Mahapragya during Jain Agamas research
Jain scriptures
–
Sacred Jain Books in a Temple Library
Jain scriptures
–
Folio from a
Kalpasutra (Book of Sacred Precepts), c. AD 1400
28.
Ancient Rome
–
In its many centuries of existence, the Roman state evolved from a monarchy to a classical republic and then to an increasingly autocratic empire. Through conquest and assimilation, it came to dominate the Mediterranean region and then Western Europe, Asia Minor, North Africa and it is often grouped into classical antiquity together with ancient Greece, and their similar cultures and societies are known as the Greco-Roman world. Ancient Roman civilisation has contributed to modern government, law, politics, engineering, art, literature, architecture, technology, warfare, religion, language and society. Rome professionalised and expanded its military and created a system of government called res publica, the inspiration for modern republics such as the United States and France. By the end of the Republic, Rome had conquered the lands around the Mediterranean and beyond, its domain extended from the Atlantic to Arabia, the Roman Empire emerged with the end of the Republic and the dictatorship of Augustus Caesar. 721 years of Roman-Persian Wars started in 92 BC with their first war against Parthia and it would become the longest conflict in human history, and have major lasting effects and consequences for both empires. Under Trajan, the Empire reached its territorial peak, Republican mores and traditions started to decline during the imperial period, with civil wars becoming a prelude common to the rise of a new emperor. Splinter states, such as the Palmyrene Empire, would divide the Empire during the crisis of the 3rd century. Plagued by internal instability and attacked by various migrating peoples, the part of the empire broke up into independent kingdoms in the 5th century. This splintering is a landmark historians use to divide the ancient period of history from the pre-medieval Dark Ages of Europe. King Numitor was deposed from his throne by his brother, Amulius, while Numitors daughter, Rhea Silvia, because Rhea Silvia was raped and impregnated by Mars, the Roman god of war, the twins were considered half-divine. The new king, Amulius, feared Romulus and Remus would take back the throne, a she-wolf saved and raised them, and when they were old enough, they returned the throne of Alba Longa to Numitor. Romulus became the source of the citys name, in order to attract people to the city, Rome became a sanctuary for the indigent, exiled, and unwanted. This caused a problem for Rome, which had a large workforce but was bereft of women, Romulus traveled to the neighboring towns and tribes and attempted to secure marriage rights, but as Rome was so full of undesirables they all refused. Legend says that the Latins invited the Sabines to a festival and stole their unmarried maidens, leading to the integration of the Latins, after a long time in rough seas, they landed at the banks of the Tiber River. Not long after they landed, the men wanted to take to the sea again, one woman, named Roma, suggested that the women burn the ships out at sea to prevent them from leaving. At first, the men were angry with Roma, but they realized that they were in the ideal place to settle. They named the settlement after the woman who torched their ships, the Roman poet Virgil recounted this legend in his classical epic poem the Aeneid
Ancient Rome
–
Senātus Populus que Rōmānus
Ancient Rome
–
Roman Republic
Ancient Rome
–
According to legend,
Rome was founded in 753 BC by
Romulus and Remus, who were raised by a she-wolf.
Ancient Rome
–
This bust from the
Capitoline Museums is traditionally identified as a portrait of
Lucius Junius Brutus.
29.
Ibn Sina
–
Avicenna or Ibn Sīnā was a Persian polymath who is regarded as one of the most significant thinkers and writers of the Islamic Golden Age. Of the 450 works he is known to have written, around 240 have survived, in 1973, Avicennas Canon Of Medicine was reprinted in New York. Besides philosophy and medicine, Avicennas corpus includes writings on astronomy, alchemy, geography and geology, psychology, Islamic theology, logic, mathematics, physics and poetry. Avicenna is a Latin corruption of the Arabic patronym Ibn Sīnā, meaning Son of Sina, however, Avicenna was not the son, but the great-great-grandson of a man named Sina. His full name was Abū ʿAlī al-Ḥusayn ibn ʿAbd Allāh ibn al-Ḥasan ibn ʿAlī ibn Sīnā, Ibn Sina created an extensive corpus of works during what is commonly known as the Islamic Golden Age, in which the translations of Greco-Roman, Persian, and Indian texts were studied extensively. Under the Samanids, Bukhara rivaled Baghdad as a capital of the Islamic world. The study of the Quran and the Hadith thrived in such a scholarly atmosphere, philosophy, Fiqh and theology were further developed, most noticeably by Avicenna and his opponents. Al-Razi and Al-Farabi had provided methodology and knowledge in medicine and philosophy, Avicenna had access to the great libraries of Balkh, Khwarezm, Gorgan, Rey, Isfahan and Hamadan. Various texts show that he debated philosophical points with the greatest scholars of the time, aruzi Samarqandi describes how before Avicenna left Khwarezm he had met Al-Biruni, Abu Nasr Iraqi, Abu Sahl Masihi and Abu al-Khayr Khammar. Avicenna was born c. 980 in Afshana, a village near Bukhara, the capital of the Samanids, a Persian dynasty in Central Asia and Greater Khorasan. His mother, named Setareh, was from Bukhara, his father, Abdullah, was a respected Ismaili scholar from Balkh and his father worked in the government of Samanid in the village Kharmasain, a Sunni regional power. After five years, his brother, Mahmoud, was born. Avicenna first began to learn the Quran and literature in such a way that when he was ten years old he had learned all of them. According to his autobiography, Avicenna had memorised the entire Quran by the age of 10 and he learned Indian arithmetic from an Indian greengrocer, ءMahmoud Massahi and he began to learn more from a wandering scholar who gained a livelihood by curing the sick and teaching the young. He also studied Fiqh under the Sunni Hanafi scholar Ismail al-Zahid, Avicenna was taught some extent of philosophy books such as Introduction s Porphyry, Euclids Elements, Ptolemys Almagest by an unpopular philosopher, Abu Abdullah Nateli, who claimed philosophizing. As a teenager, he was troubled by the Metaphysics of Aristotle. For the next year and a half, he studied philosophy, in such moments of baffled inquiry, he would leave his books, perform the requisite ablutions, then go to the mosque, and continue in prayer till light broke on his difficulties. Deep into the night, he would continue his studies, and even in his dreams problems would pursue him and work out their solution
Ibn Sina
–
Conventional modern portrait (on a silver vase,
Avicenna Mausoleum and Museum,
Hamadan)
Ibn Sina
–
A drawing of Avicenna from 1271 [
citation needed]
Ibn Sina
–
The first page of a manuscript of Avicenna's Canon, dated 1596/7 (Yale, Medical Historical Library, Cushing Arabic ms. 5)
Ibn Sina
–
Gravestone of Avicenna
30.
The Canon of Medicine
–
The Canon of Medicine is an encyclopedia of medicine in five books compiled by Persian philosopher Avicenna and completed in 1025. It presents an overview of the medical knowledge, which had been largely influenced by Galen. The Canon of Medicine remained an authority for centuries. It set the standards for medicine in Medieval Europe and the Islamic world and was used as a medical textbook through the 18th century in Europe. It is still used in Yunani medicine, a form of medicine practiced in India. The English title The Canon of Medicine is a translation of the Arabic title القانون في الطب, the word Canon derives from the cognate Arabic original Qanun. The medical traditions of Galen and thereby Hippocrates, had dominated Islamic medicine from its beginnings, Avicenna sought to fit these traditions into Aristotles natural philosophy. He began writing the Canon in Gorganj, continued in Rey, the result was a clear and ordered summa of all the medical knowledge of Ibn Sīnās time It served as a more concise reference in contrast to Galens twenty volumes of medical corpus. The Canon of Medicine is divided into five books, Essays on basic medical and physiological principles, anatomy, regimen, list of medical substances, arranged alphabetically, following an essay on their general properties. Diagnosis and treatment of diseases specific to one part of the body Diagnosis, the book explains the causes of health and disease. Avicenna believed that the body cannot be restored to health unless the causes of both health and disease are determined. In other words, it is the art whereby health is concerned, Avicenna begins part one by dividing theoretical medicine and medical practice. Efficient Cause The efficient cause is broken up into two categories, The first is Extrinsic, or the external to the human body such as air or the region we live in. The second efficient cause is the Intrinsic, or the sources such as our sleep and its opposite-the waking state, the different periods of life, habits. Formal Cause The formal cause is what Avicenna called the constitutions, final Cause The final cause is given as the actions or functions. Avicennas thesis on the elements of the cosmos is described by Gruner as the foundation of the whole Canon, the elements we experience are mixed with small amounts of other elements and are therefore not the pure elemental substances. The light elements are fire and air, while the heavy are earth and water, the Earth is at rest, and other things tend towards it because of its intrinsic weight. The Water Water is described as being exterior to the sphere of the Earth and interior to the sphere of the Air, being moist, shapes can be readily fashioned, and as easily lost
The Canon of Medicine
–
Persian version of The Canon of Medicine at
Avicenna's mausoleum in
Hamedan
The Canon of Medicine
–
First page of the introduction to the first book (Arabic manuscript, 1597)
The Canon of Medicine
–
A
Latin copy of the Canon of Medicine, dated 1484, located at the P.I. Nixon Medical Historical Library of the
University of Texas Health Science Center at San Antonio.
The Canon of Medicine
–
East Asian
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. PMID 7535888.
